The subject of the present invention relates to the field of motorized vehicles, in particular to an actuator device for motorcycle stands, or stands for other vehicles, such as scooters.
More particularly, the invention relates to a improved actuator device that, in addition to lifting the vehicle on the stand, allows the driver to operate the stand in a manner opposite to that of lifting, thus also making easier the maneuver of lowering the vehicle from the stand.
In motorcycles and in scooters, the maneuver of lifting the vehicle on the stand always requires a certain physical force and is often tough.
An actuator device with an electro-hydraulic drive system is known that solves the problem, as described in U.S. patent application Ser. No. 09/664,251 in the name of the same applicant. This system is based on a flow control valve that operates an actuator by emptying the actuator at the end of the maneuver or in case of interruption of the lifting maneuver.
In big motorcycles and in some types of scooters, where the driver is tied by special safety belts, the driver needs a way to make easier the lowering of the vehicle from the stand. This need is felt much more in the case of sloped parking; in this case, in fact, the effort needed for lowering the vehicle from the stand is much greater.
Typically, the moment of the weight of the vehicle with respect to the stand""s axis of articulation is approximately zero degrees at the dead point before the vehicle reaches its steady position on the stand. For this reason, when lowering the vehicle from the stand, it is necessary to have a short movement for reaching the dead point after which the vehicle lowers spontaneously.
The object of the present invention is to provide a device for actuating a motorcycle stand, or stands for other vehicles such as scooters, that is driven electro-hydraulically and operates the stand for lifting. Furthermore, the object of the present invention is to provide a device that makes easier the step of lowering the motorcycle, or other vehicle, from the stand, even allowing a normal step of lowering the stand.
It is a particular object of the present invention to provide an actuator device that operates the stand throughout the lifting maneuver and also allows the reverse maneuver in order to rotate the stand from its position when the motorcycle, or other vehicle, is on the stand to when the vehicle lowers spontaneously.
It is a particular object of the present invention to provide an actuator device that allows the stand to move freely between the position of the motorcycle, or other vehicle, on the stand and the rest position of the vehicle off the stand independent from the actuator device, providing substantially the same functionality of a traditional stand.
A further object of the present invention is to provide an electro-hydraulic circuit for motorcycle stands that can be used for said actuator device.
These and other objects are achieved by the actuator device as defined in the attached claims.
According to the invention, a device for actuating the rotation of a motorcycle stand comprises at least a hydraulic actuator operating an actuating member between a first rest position and a second standing position, by a hydraulic flow control circuit, so that the motorcycle stand is in any case moved from the standing position to the rest position independently from the actuating member. The characteristic of the device is that when the motorcycle stand is in the second standing position, and the actuating member is then turned back to the first rest position, means are provided by the actuator for starting the return rotation of the stand from the second standing position to the first rest position up to a point wherein it is not necessary to bear the weight of the vehicle for carrying out the rotation.
Preferably, the actuator device is a hydraulic cylinder comprising a piston and the actuating member is a piston rod sliding in the motorcycle stand and connected to the piston, the piston rod moving between an extended position corresponding to the first rest position to a retracted second standing position, whereby the motorcycle stand is brought to the second standing position by pulling the piston rod through an abutting end of the latter.
Advantageously, the means for starting the return rotation of the stand comprise a pushing element in the hydraulic cylinder having a tubular portion sliding coaxially on the piston rod and having an end external to the hydraulic cylinder suitable for urging a lever integral to the stand, the piston pushing the motorcycle stand independently from the piston rod by pressure against the pushing element.
The pushing element preferably has a head suitable for urging the piston and resilient means set between the head and the bottom of the hydraulic cylinder that oppose the movement of the tubular portion towards the motorcycle stand.
Alternatively, the actuator device can be a hydraulic cylinder comprising a piston and the actuating member is a piston rod sliding in the motorcycle stand and connected to the piston, the piston rod moving between an extended position corresponding to the second standing position to a retracted first rest position, whereby the motorcycle stand is brought to the standing position by the piston rod through a first abutment that pushes the motorcycle stand.
The means for starting the return rotation of the motorcycle stand comprise a second abutment provided at the end of the piston rod distanced by the first abutment, whereby the piston rod pushes by the first abutment causing the motorcycle stand to move from the first rest position to the second standing position and pulls by the second abutment causing the back stroke of the motorcycle stand towards the first rest position, the distance between the first and second abutment allowing the motorcycle stand to complete the movement of back stroke to the first rest position independently by the piston.